抄録
Acyl-CoA synthetase was estimated as an amount of acyl-CoA synthesis from radioactive palmitic acid in the presence of ATP, CoASH, and MgCl2.
Characteristics of acyl-CoA synthetase in arterial wall extract were examined. Km values for palmitate or ATP or CoASH or Mg2+ were 0.29, 3.45, 0.03, 4.0mM, respectively. The optimum pH was around 8.0 and the highest specific activity was found in microsomal fraction. These characteristics were almost similar to those of liver acyl-CoA synthetase.
Acyl-CoA synthetase was inhibited by divalent cations such as Cu2+, Fe2+, Zn2+ and Ca2+ and was activated by serum, bovine serum albumin and lipoproteins. Changes of these enzyme activities were found in some pathological conditions. Increase in aged or hypercholesterolemic rat was found and in experimental hypertensive or diabetic or tocopherol deficient condition, the activities were found to be decreased. The relationship between regulatory factors and changes of this enzyme activities in pathological conditions was discussed.
